Arrested development of the myxozoan parasite, Myxobolus cerebralis, in certain populations of mitochondrial 16S lineage III Tubifex tubifex

• Published in: Parasitology research (1987) Vol. 102; no. 2; pp. 219 - 228
• Main Authors: Baxa, D. V, Kelley, G. O, Mukkatira, K. S, Beauchamp, K. A, Rasmussen, C, Hedrick, R. P
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Berlin/Heidelberg : Springer-Verlag 01.01.2008; Springer-Verlag; Springer
• Subjects: Animals; Biological and medical sciences; Biomedical and Life Sciences; Biomedicine; DNA, Mitochondrial - genetics; DNA, Ribosomal Spacer - analysis; DNA, Ribosomal Spacer - genetics; Eukaryota - growth & development; Eukaryota - isolation & purification; Eukaryota - pathogenicity; Eukaryota - physiology; Fundamental and applied biological sciences. Psychology; General aspects; General aspects and techniques. Study of several systematic groups. Models; Genetic Variation; Host-Parasite Interactions; Immunology; Invertebrates; Medical Microbiology; Microbiology; Myxobolus cerebralis; Oligochaeta; Oligochaeta - classification; Oligochaeta - genetics; Oligochaeta - parasitology; Original Paper; Polymerase Chain Reaction; Random Amplified Polymorphic DNA Technique; RNA, Ribosomal, 16S - genetics; Spores, Protozoan; Tubifex; Tubifex tubifex; Clonal Line; Parasite Production; Myxozoan Parasite; Cohabitation Experiment; Whirling Disease; Myxozoa; Tubifex tubifex; Mitochondria; Development; Parasite; Invertebrata; Annelida; Oligochaeta
• ISSN: 0932-0113; 1432-1955
• DOI: 10.1007/s00436-007-0750-1

Laboratory populations of Tubifex tubifex from mitochondrial (mt)16S ribosomal DNA (rDNA) lineage III were generated from single cocoons of adult worms releasing the triactinomyxon stages (TAMs) of the myxozoan parasite, Myxobolus cerebralis. Subsequent worm populations from these cocoons, referred to as clonal lines, were tested for susceptibility to infection with the myxospore stages of M. cerebralis. Development and release of TAMs occurred in five clonal lines, while four clonal lines showed immature parasitic forms that were not expelled from the worm (non-TAM producers). Oligochaetes from TAM- and non-TAM-producing clonal lines were confirmed as lineage III based on mt16S rDNA and internal transcribed spacer region 1 (ITS1) sequences, but these genes did not differentiate these phenotypes. In contrast, random amplified polymorphic DNA analyses of genomic DNA demonstrated unique banding patterns that distinguished the phenotypes. Cohabitation of parasite-exposed TAM- and non-TAM-producing phenotypes showed an overall decrease in expected TAM production compared to the same exposure dose of the TAM-producing phenotype without cohabitation. These studies suggest that differences in susceptibility to parasite infection can occur in genetically similar T. tubifex populations, and their coexistence may affect overall M. cerebralis production, a factor that may influence the severity of whirling disease in wild trout populations.